1. This invention is related to a disposable hand tool for cutting plastic optical fiber cable known as POF and to an hand tool with disposable cutting blade.
2. Description of the Prior Art
There are not too many hand held cutting tools made for POF, mostly are small “in palm” sized plastic molded tool, including a thin blade or a razor in a range of 0.2˜0.5 mm thick, comprising row of holes that fit the thickness of a commonly used single POF cable (such as 2.2 mm diameter) or of a commonly used twin core POF cable with each of the twin cable diameter is 2.2 mm. The cutters are all operating in a guillotine style wherein the POF cable is inserted into one of a single hole or twin holes and the blade or the razor is pushed toward the cable to cut it perpendicular to the cable length, providing smooth cut surface.
To provide smooth cut without scratches, cracks or other deformed surfaces the blade's edge should be used only once per cut. This was proven time and again that the edge is damaged by the cut and when the blade's sharp edge is used more than once, the cuttings become unreliable. The repeated use of the sharp edge by cutting the POF through the same given hole is a cause for scratches, cracks and uneven surfaces of the core itself, moreover it creates residues of hanging whiskers of the core's cladding and of the cable protective cover, some of which may adhere onto the cut surface plane of the core. The optical characteristics and the performances of the plastic optical fiber (POF) cable are severely affected by the defects caused by the repeated use of the blade's edge and such repeated cuttings should be prevented.
Literally all of the known disposable hand cutting tool provide only instruction and warning not to use the same hole twice, but do nothing to prevent a repeated cutting through the same hole. The warning is a failed solution, because users genuinely forget which of the holes is already used and unintentionally re-use the same hole.
Some are searching for a solution and an hand tool for cutting POF by a blade with a mechanism for preventing repeated cutting by the same sharp edge portion is disclosed in US application 2010/0187276 dated Jul. 29, 2010. However the disclosed hand tool introduces complex mechanism for such simple cutting operation. The disclosed hand tool of the application 2010/0187276 is a complex structure and a cumbersome to configure and operate. Moreover, such hand tool if it will become available it will be too expensive for a disposable type, and a simpler far less complex and far less costly solution is needed.